Ignore the treasure on the top section for now. Run to A and grab the bucket there. When the monk is at about B, drop down to point C and use the slime on the floor to your left. Get the bucket at D, drop down and use it to slime the tiles labeled E. Get the bucket at F and use it to slime the tiles labeled G. Run to H and wait as long as you can, then race to the ladder to the right. When you get to J, the monks above you will run away from you, so that gives you a bit of precious extra time. Now climb up the ladder, possibly grabbing a couple of treasures along the way, and get back to the top section.
Get another slime bucket and use it while standing at D to cover the tiles labeled K. Drop down and wait at point L as long as you can (until the lead monk is near the center of the 'K' tiles). The drop down to get all the treasure, and again race to the ladder on your right. Climb back up the ladder and return to the top section.
Now you can get all the treasures up here. You may have to make several return trips to the bottom to collect the rest of the treasures, but it shouldn't be too hard now that the whole platform is slimed, and the difficult treasures below L have been retrieved.
When you get all the treasure, don't bother using the ladders that appear; just dig through at, say, point C.